A GRATING DESIGN

摘要

The present invention provides an optical device incorporating a sampled grating structure having a chirped sampling period. The present invention ma y alternatively be defined as a method of producing a grating structure in a photosensitive optical waveguide, the method comprising the step of irradiating the device with UV light at an intensity sufficient to induce refractive index variations in the waveguide in a manner to produce a sample d grating structure, and wherein the radiation is controlled in a manner to effect chirping of the sampling period. The invention may alternatively be defined as providing a group delay dispersion compensator device comprising a sampled grating structure a having chirped sampling period. It has also been recognised that a method of producing a zero dispersion WDM channel can be provided.